Automatic internal pressure regulating pouring attachment



M. s. CRANE Q 2,891,702

June 23, 1959 AUTOMATIC INTERNAL PRESSURE REGULATING POURING ATTACHMENT 2 Sheets-Sheet 1 Filed Aug. 19, 1955 q a 2 u e D 2 y g mm fl C 4, i L m a 5 m Fri 2 b S a w l ,1 o l m. m m I w 4 8 2 I m June 23, 1959 T M. s. CRANE 2,891,702

AUTOMATIC INTERNAL PRESSURE REGULATING POURING ATTACHMENT Filed Aug. 19, 1955 2 Sheets-Sheet 2 IHVENTQK, Moses 3. Crane -BY i M A Home 2,891,702 Patented June 23, 1959 ice AUTOMATIC INTERNAL PRESSURE REGULATIN G POURING ATTACHMENT This invention relates to the construction of pouring attachments for substantially enclosed liquid containers having single outlet openings. The process of decanting acids and other chemically active solutions from enclosed containers is extremely diflicult. An extremely smooth flow at a controllable rate is practically a necessity if an accurately measured quantity is to be poured. The penalty for spillage during the pouring operation is rather severe, since the action of the acids or similar solutions on clothing, wooden floors, and on finished surfaces is likely to cause extensive damage.

It is the purpose of this invention to provide a pouring attachment which will maintain a smooth fiow of liquid from the principal container Without the pulsations normally accompanying the decanting operation, and at a rate of fiow which is less than that which would correspond to maintaining atmospheric pressure within the container during pouring. Pulsations in flow are the result of bubbles of air of substantial size entering into the container to displace the liquid being poured. As these bubbles break the surface of the liquid in the container, a sudden change in liquid column pressure takes place as a result of the lowered liquid level corresponding to the volume of the bubble. Inertia effects of the moving liquid, coupled with the compressibility resilience of the displacement air, tends to complicate the flow rate, once pulsation has begun. 7

It is well known to insert a vent tube in the mouth of a container to provide a channel for the admission of displacement air into the container, but the construction of such conventional equipment has generally resulted in the admission of relatively large bubbles into the liquid, tending to cause pulsations in the flow of the pouring operation to the extent that accurate measurement and control of direction is made rather difficult. The conventional vent tube is provided with an opening communicating with the interior of the principal container at a point or points adjacent to the inner end of the tube. Applicant has discovered that -a series of perforations of small diameter spaced along a considerable length of the tube will create a large number of extremely small bubbles which will supply dispacement air into the container at a sufiiciently uniform rate to cause a smooth flow of pouring discharge. The bubbles from the several openings are not formed synchronously, and consequently do not have a cumulative effect in establishing liquid pulsations. The formation takes place at a sufficiently random fashion, due partially to the substantial difference in pressure at each of the several openings resulting from the spacing, that a practically continuous flow of displacement air results.

Increases in the pouring angle of the principal container will initially create an increase in the pressure of the liquid adjacent the pouring opening, and a corresponding decrease in air pressure within the container. Such changes in pouring attitude will therefore result in a variation in the pressure differential tending to force displacement air into the interior of the container through the vent tube. As the pressure differential increases, more and more of the perforations will come into action as the pressure overcomes the surface tension of the liquid at the openings and the pressure of the liquid at that point. In addition to these over-all functional characteristics, this invention provides a particularly effective arrangement for constructing a pouring atachment of this type.

- The several features of this invention will be analyzed in detail by a discussion of the particular embodiments illustrated in the accompanying drawings. In the drawmgs:

Figure 1 presents a front view of one modification of the pouring attachment.

Figure 2 presents a side elevation of the device illustrated in Figure 1, Figures 1 and 2 being in projection.

Figure 3 presents a fragmentary sectional view showing the installation of the device illustrated in Figures 1 and 2 in the outlet opening of a container.

Figure 4 shows a schematic illustration of the pouring operation involving the container shown in Figure 3.

Figure 5 presents a view of a modified form of the pouring attachment provided by this invention. 7

Figure 6 presents a side elevation of the device shown in Figure 5, Figures 5 and 6 being in projection.

Figure 7 illustrates a fragmentary section showing the installation of a device illustrated in Figures 5 and 6 in a container.

Referring to Figures 1 through 4, inclusive,'a container 10 (in the form of a conventional steel barrel) is fitted with a pouring attachment generally indicated at 11. The attachment 117is secured in the outlet opening 12 of the container 10 through the action of a threaded cap 13 exerting a clamping effect on the flange 14 of the attachment 11 and the sealing gasket 15. The cap 13 engages similarly-formed threads in the annular portion 16 of the container which terminates in a flat section 17 for receiving the gasket 15.

The pouring attachment 11 isprovided with a cylindrical tubular portion 18 having a partition 19 which extends substantially axially and divides the cross sectional area of the tubular portion '18 into areas having preferably the ratio of approximately 2 to'3. The larger of these sections forms a passage indicated at 20 communicating with the interior of the container 10 at a point adjacent to the opening 12.

The smaller of the passages formed by the partition 19 is indicated at 21, and communicates with a vent tube 22 which is disposed inwardly from the opening 12 and extends laterally with respect thereto. The vent tube 22 is provided with a series of small perforations as indicated at 23 which are spaced axially along the length of tube 22, and are of a sufficiently small diameter as to inhibit any tendency of liquid to flow inwardly into the vent tube (particularly at the lower portions most nearly adjacent the opening 12). Under ordinary circumstances, as in the case of distilled water, sulfuric acid, and similar liquids and solutions, the diameter of the openings 23 may be on the order of a 32nd to a 16th of an inch, and should be distributed along a distance of 4 to 6 inches of the length of the vent tube 22. The perforated tube 22 may well extend to within one-half inch of the uppermost side of the container (in pouring position), as the positioning of the uppermost perforation 23 at a point of minimum liquid pressure seems to be desirable. Under these circumstances, the movement of the container 10 to the pouring position illustrated in Figure 3 will result in the smooth discharge of liquid through the passage 20 as the result of the formation of large numbers of minute bubbles and the discharge thereof through the openings 3 23, which are established in a sufiiciently random fashion to create a smooth flow of displacement air and the consequent absence of a pulsation of liquid flow through the'passage 20.

It is necessary to establish a relationship between the number and size of the perforations 23 and the characteristics of the pouring passage 26. Too small an admission of air through the vent tube will tend to make the device draw air in through the pouring passage 2% as if there were no vent tube. Rates of pouring, characteristics of the particular liquid, and the length and cross-section of the passage 20 will influence this relationship. In the case of conventional containers for hydrochloricacid, sulphuric acids, distilled water, and the like, applicant has found that a tubular portion 13 of about 18 millimeters in inside diameter divided so that the-pouring. passage 20 occupies about sixty percent of the total area, formed in the illustrated proportions, works very effectively when eight perforations of three sixtyfourtbs of an inch in diameter are used on the tube, spaced on one-half inch centers. The ratio of the cross sectional areas of the passage 21 to that of the passage 20 should be greater than about one to three, and this ratio is preferably two to three, as noted previously. If the ratio of the cross sectional areas at the plane indicated at 24 is much smaller than one to three, there is likely to be a tendency for the relatively high velocity air inflow to suck quantities of liquid into the air passageway, and to sufficiently block the air fiow to create pulsations.

Referring to Figures 5, 6, and 7, a pouring attachment is illustrated which operates on generally the same principles as that of the device shown in Figures 1 through 4, inclusive. A preferably cylindrical tubular portion 25 is formed so that it may be inserted in the opening defined by the annular portion 26 of the container 27, where it is held in position through the action of a threaded cap 28 exerting a clamping effect on the flange 29 and the sealing gasket 30. In the modification shown on Figures 5, 6, and 7, the outlet of the tubular portions 25 is threaded and is engaged by a similarly threaded cap 31.

The vent tube portion of the modification shown in Figures 5 through 7 is formed by a continuation of a portion of the tubular section 25 and the partition 33. In the manufacturing of the device, a tube of a diameter of the section 25 is selected and cut off to a length sufiicient to include both the tubular section 25 and the vent tube section 32. A cut is then made along a plane slightly diverging from the axis of the tube which creates a tapered portion of generally cylindrical curvature, and the extension of the partition 33 is secured thereto as by soldering to form a continuous conduit. The tube can then be bent into the attitude shown in Figure 6, or the bending can take place prior to the soldering. It will be noted that the partition 33 and the partition 19 are both concave on the side traversed by the liquid. This arrangement tends to provide the most desirable fluidfiow characteristics, and also facilitates draining the air passage. The convex surface on the air passage side of 1- the partitions urges entrapped liquid to either side of the passage so that it may move out during pouring without blocking airflow. The vent tube portion 32 is provided with perforations indicated at 34 similar in size and distribution to those of the perforations 23 illustrated in Figures 1, 2, and 3.

The particular embodiments of the present invention which have been discussed and illustrated herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims.

I claim:

1. A pouring attachment for a container having a relatively small outlet opening comprising a tubular cylindrical portion adapted to engage and extend horizontally through said outlet opening, means for maintaining a seal between the exterior of said tubular portion and said container, means forming an axially extending partition in said tubular portion, said partition means dividing the cross-section of said tubular portion into a lower major area and an upper minor area, the ratio of said minor area to said major area being at least one-to-three, said partition being concave on the side of the major area and convex on the side of the minor area, the major area section providing a liquid outlet section communicating with the interior of said container adjacent said outlet opening, and a vent tube, convex on its upper side and concave on its lower side, said upper convex side extending integrally longitudinally from the upper side of said tubular cylindrical portion, said lower concave side extending integrally longitudinally from said partition, said upper and lower sides being integrally joined together along their two edges providing an inverted crescentshaped cross sectional area, said vent communicating with the minor area section above said major area section and curving upwardly in an are from the axis of said tubular cylindrical portion, said vent tube terminating in a substantially closed inner end, said vent having a plurality of spaced apart small diameter perforations in said upper convex side below its closed end, said perforations being each located at a different distance from said closed end.

2. The pouring attachment of claim 1, said vent tube being of progressively smaller cross-sectional area as it curves upwardly.

References Cited in the file of this patent UNITED STATES PATENTS 657,274 Ritz Sept. 4, 1900 1,492,501 Whitesides Apr. 29, 1924 1,971,284 Stockman Aug. 21, 1934 2,281,135 Becker Apr. 28, 1942 2,424,101 Lari July 15, 1947 2,501,636 Smith Mar. 21, 1950 2,759,642 Rickard Aug. 21, 1956 FOREIGN PATENTS 22,299 Great Britain of 1901 

